The present invention relates to a disk device such as a magnetic hard disk drive and the like.
Conventionally, as one type of hard magnetic disk devices, a magnetic hard disk drive which conforms to the Personal Computer Memory Card International Association (PCMCIA) xe2x80x9cType II standardsxe2x80x9d is known. This hard magnetic disk device comprises a mechanism part where a movable part exists and an electric circuit part for controlling this mechanism part. The mechanism part forms a shielded space and the electric circuit part is arranged outside this shielded space.
In the mechanism part, an actuator as the movable part is provided inside a frame body. This actuator causes a magnetic head for recording and reproducing information to shift with respect to a magnetic disk on and from which information is recorded and reproduced. The frame body is covered by a top cover. This top cover has an adhesive portion on the peripheral portion thereof, is adhered to the frame body by this adhesive portion, and shields the interior space thereof.
However, the following problems exist in such well-known devices.
Due to nonconformity in components and/or assembly, some devices need to be repaired after assembly before being placed on the market. However, the sealing structure of the device is constructed by, as mentioned above, adhering the top cover having the adhesive portion to the frame body, and when the top cover is opened for repairing the device, deformation occurs to the top cover, and the top cover cannot be reused. In this case, since the top cover is not low-priced, there is a problem such that the price of the device is raised.
The electric circuit part is assembled by means of a printed circuit board (hereinafter, referred to as a xe2x80x9cPCBxe2x80x9d). In the device, in order to cause an actuator to generate sufficient torque, a magnetic circuit for driving this actuator is thickly formed. In addition, the PCB is constructed while avoiding these thick components.
On the other hand, in recent years, a method (a ramp loading method) has been employed, wherein a magnetic head is evacuated to the outside of a magnetic disk during the non-operating time of a device. In the ramp loading method, since the magnetic head is evacuated to the outside of the magnetic disk, the rotation angle of the actuator increases. Then, inevitably, components forming the magnetic circuit become large.
Therefore, if the ramp loading method is employed in the well-known device, it is necessary to cut away the PCB greatly. As a result, the area for mounting electronic components decreases and a problem occurs such that these electronic components cannot be mounted or connection of an electric circuit becomes impossible. Meanwhile, if the mounting area of the PCB is secured, a problem occurs such that the ramp loading method cannot be employed or a voice coil motor becomes thin and it becomes impossible to cause the actuator to generate sufficient torque.
The present invention is made to solve such problems in the prior art, and it is an object of the invention to construct a disk device such as a magnetic hard disk drive at a low price, and in a low-profile device as well, to efficiently arrange a mechanism portion and an electric circuit portion so as to enable an actuator to generate sufficient torque.
In order to achieve this object, in a disk device with a disk arranged inside a frame body according to the present invention, a cover is placed on the frame body, a gap is formed between a rim of the cover and the frame body, and the gap is shielded by a sheet having an adhesive portion.
According to the present invention, in compliance with the PCMCIA Type II standards, a magnetic hard disk is formed such that a peripheral portion thereof is thinner in thickness than a central portion thereof, and includes an interface connector at an end portion thereof, wherein a printed circuit board is provided in the thick central portion of the disk, and the interface connector is provided formed with horn-shaped connecting portions to the printed circuit board. The horn-shaped connecting portions are formed in a protruded manner so as to reach the thick central portion.
In a disk device with a disk arranged inside a frame body according to the present invention, the peripheral portion is formed to be thinner than the central portion, a printed circuit board is provided in the thick central portion, and a surface of the printed circuit board for mounting electric components on the printed circuit board is a surface on the frame body side.
In addition, the disk device with a disk arranged inside a frame body according to the present invention comprises an actuator provided for driving a head for recording and reproducing information on and from the disk, which actuator is composed of a voice coil motor comprising a pair of yokes opposed to each other with a predetermined distance therebetween, a movable coil wound to be movable between the yokes, and a permanent magnet attached to at least one of the yokes to add a magnetic field to the movable coil. Further, one of the yokes forms a part of an outer wall of the frame body, in place of the frame body.
In a disk device with a disk arranged inside a frame body according to the present invention, an actuator is provided for driving a head for recording and reproducing information on and from the disk, the actuator being composed of a voice coil motor comprising a pair of yokes opposed to each other with a predetermined distance therebetween, a coil wound to be movable between the yokes, and a permanent magnet attached to at least one of the yokes to add a magnetic field to the movable coil, and each or the yoke is formed to be thick at a part corresponding to a section between two poles of the permanent magnet and a vicinity thereof, and is formed, at the other part, to be thinner than the thick part.
Thus, according to the present invention, even in the low-profile disk device, by efficiently arranging the mechanism portion and the electric circuit portion, the actuator can be caused to generate sufficient torque.
In detail, according to the disk device of the present invention, the gap is formed between the rim of the cover and the frame body, and this gap is closed by means of the sheet having the adhesive portion. Therefore, when repairing the device, it is sufficient to replace only the inexpensive sheet having an adhesive portion.
According to the present invention, by forming a hole on the sheet, component members of the disk device such as mechanical components and the like can be arranged in this hole. With such a structure, the component members of the disk device such as mechanical components can be provided to a large extent and performance of the device can be enhanced.
In the magnetic hard disk drive of the present invention, horn-shaped connecting portions to the PCB, which have been formed in a protruded manner so as to reach the thick central portion of the disk device, are formed on the interface connector, so that the PCB can be disposed on the lower side than a part having a thickness of 3.3 mm. As a result, on the PCB with the IC-mounting surface being on the frame body side, component members of the disk device such as mechanism components can be arranged between the ICs. Furthermore, even when a ramp loading method is employed, which has been employed in recent years for improvement in impact resistance of the device, achievement of lower power consumption and higher recording density, the voice coil motor can be made thick without reducing the mounting area of the PCB and the actuator can be caused to generate sufficient torque.
According to the present invention, since the connecting part between the interface connector and the PCB is low in rigidity, connecting portions are provided for fixing this interface connector to the frame body with screws. As a result, even if an impact is applied to the interface connector, the electrical connecting part of the interface connector can be prevented from being detached.
According to the disk device of the present invention, the hole in which the permanent magnet is placed is made on the frame body and also the yoke is provided in place of the wall part of this frame body. Thus, the magnetic circuit portion can be made thick and torque generated in the actuator can be increased.
According to the present invention, bosses having screwing margins are provided inside the frame body and the yoke is constructed so as to be fixed by screws to the frame body from the rear side of the frame body. As a result, without reducing the IC-mounting area of the PCB, the yoke can be screwed. This screw tightening allows it to replace the yoke alone.
The disk device of the present invention can be provided with concave portions for embedding screw heads in the yoke. As a result, since the screw heads do not project, ICs can be mounted on the PCB at a position corresponding to the concave portions.
The present invention enables it to thinly form other parts of the yoke than the vicinity of a part corresponding to the central part of the permanent magnet. Therefore, ICs can be mounted on the PCB at a position corresponding thereto. As a result, without reducing the IC-mounting area, the actuator can be caused to generate great torque.
According to the disk device of the present invention, the interior of the device can be shielded by closing the gap between the lower yoke and the frame body by means of the sheet having the adhesive portion. This sheet has a hole in the central part. The thick part of the yoke is inserted into this hole. As a result, while employing the shielding structure, without reducing the IC-mounting area, the actuator can be caused to generate great torque.